Source: Adelson gives $1 million to pro-Connie Mack super PAC

6/19/12 12:20 PM EDT

Sheldon Adelson is giving $1 million to the super PAC backing Rep. Connie Mack in his Senate bid in Florida, a source familiar with the donation said.

It's the latest detail about where Adelson, the biggest single donor to super PACs this cycle, is spreading his money, of which he has told allies he plans to spend around $100 million this cycle.

It wasn't immediately clear whether the donation has happened or is a pledge to Freedom PAC.

An Adelson spokesman declined comment. Rob Cole, a senior adviser to Freedom PAC, wouldn't confirm or deny the expected cash. He would say only that fundraising is going "extremely well" and that Mack "expects to beat Democratic Sen. Bill Nelson in the fall."

Before he gets there, he has to make it through a competitive multicandidate primary. He's also gotten the backing of FreedomWorks in the race.